The field of the present invention is exhaust timing control devices for two cycle engines.
Japanese Utility Model Publication No. 51-39112 (39112/1976), the disclosure of which is incorporated herein by reference, discloses an exhaust timing control device which controls the initiation of the exhaust cycle in a two cycle engine to increase power. This exhaust timing control device is provided with a member which can move to a position on an upper portion of an exhaust port in a two cycle engine. In this position, the member controls the timing edge location of the exhaust port in accordance with the speed of the engine to adjust the exhaust timing.
Japanese Utility Model Publication No. 52-132916, the disclosure of which is incorporated herein by reference, discloses another exhaust timing control device. The device senses the operational position of an operating member in the driving mechanism for the exhaust timing member relative to a reference position. From this, the position of the exhaust timing member is controlled according to the engine speed.
In the foregoing devices, the exhaust timing is responsive solely to engine rotational speed. Naturally, a variety of other parameters of engine operation can affect optimum exhaust timing in addition to engine speed.